<?php
namespace org\wechat;  
  
class Jssdk{  
  
    private $appId;  
    private $appSecret;  
    private $path;  
  
    public function __construct($appId, $appSecret) {  
        $this->appId = $appId;  
        $this->appSecret = $appSecret;  
        $this->path = __DIR__.DS;
    }  
  
    public function getSignPackage() {  
        $jsapiTicket = $this->getJsApiTicket();  
  
        // 注意 URL 一定要动态获取，不能 hardcode.  
        $protocol = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' || $_SERVER['SERVER_PORT'] == 443) ? "https://" : "http://";  
        $url = "$protocol$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";  
  
        $timestamp = time();  
        $nonceStr = $this->createNonceStr();  
  
        // 这里参数的顺序要按照 key 值 ASCII 码升序排序  
        //$string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr×tamp=$timestamp&url=$url";
        $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url";


  
        $signature = sha1($string);
  
        $signPackage = array(  
            "appId"     => $this->appId,  
            "nonceStr"  => $nonceStr,  
            "timestamp" => $timestamp,  
            "url"       => $url,  
            "signature" => $signature,  
            "rawString" => $string  
        );  
        return $signPackage;  
    }  
  
    private function createNonceStr($length = 16) {  
        $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";  
        $str = "";  
        for ($i = 0; $i < $length; $i++) {  
            $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);  
        }  
        return $str;  
    }  
  
    public function getJsApiTicket() {  
        // jsapi_ticket 应该全局存储与更新，以下代码以写入到文件中做示例  
        $data = json_decode($this->get_php_file("jsapi_ticket.php"));  
        if ($data->expire_time < time()) {  
            $accessToken = $this->getAccessToken();  
            // 如果是企业号用以下 URL 获取 ticket  
//            $url = "https://qyapi.weixin.qq.com/cgi-bin/get_jsapi_ticket?access_token=$accessToken";  
            $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";  
            $res = json_decode($this->httpGet($url));  
            $ticket = $res->ticket;  
            if ($ticket) {  
                $data->expire_time = time() + 7000;  
                $data->jsapi_ticket = $ticket;  
                $this->set_php_file("jsapi_ticket.php", json_encode($data));  
            }  
        } else {  
            $ticket = $data->jsapi_ticket;  
        }  
  
        return $ticket;  
    }  
  
    public function getAccessToken() {  
        // access_token 应该全局存储与更新，以下代码以写入到文件中做示例  
        $data = json_decode($this->get_php_file("access_token.php"));  
        if ($data->expire_time < time()) {  
            // 如果是企业号用以下URL获取access_token  
//             $url = "https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid=$this->appId&corpsecret=$this->appSecret";  
            $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$this->appId&secret=$this->appSecret";  

            $res = json_decode($this->httpGet($url));

            $access_token = $res->access_token;  
            if ($access_token) {  
                $data->expire_time = time() + 7000;  
                $data->access_token = $access_token;  
                $this->set_php_file("access_token.php", json_encode($data));  
            }  
        } else {  
            $access_token = $data->access_token;
        }  
        return $access_token;  
    }  
  
    private function httpGet($url) {  
        $curl = curl_init();  
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);  
        curl_setopt($curl, CURLOPT_TIMEOUT, 500);  
        // 为保证第三方服务器与微信服务器之间数据传输的安全性，所有微信接口采用https方式调用，必须使用下面2行代码打开ssl安全校验。  
        // 如果在部署过程中代码在此处验证失败，请到 http://curl.haxx.se/ca/cacert.pem 下载新的证书判别文件。  
        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, 2);  
        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, 2);  
        curl_setopt($curl, CURLOPT_URL, $url);  
  
        $res = curl_exec($curl);  
        curl_close($curl);  
  
        return $res;  
    }  
  
    private function get_php_file($filename) {  
        return trim(substr(file_get_contents($this->path.$filename), 15));  
    }  
    private function set_php_file($filename, $content) {  
        echo 9;  
        $fp = fopen($this->path.$filename, "w");  
        fwrite($fp, "<?php exit();?>" . $content);  
        fclose($fp);  
    }  
  
}  
